Methane production from horse manure and stall waste with softwood bedding

► Methane potential for three batches of horse manure was 68, 191 and 273 mL/g volatile solids (VS). ► Energy production from 1:1 mixtures of softwood bedding to manure was 1.7-3.9 kJ/metric ton wet weight. ► One horse producing 12 metric tons waste per year could yield 2-4.7 GJ methane energy per year. ► Softwood bedding was barely degradable and diluted the energy production of the stall waste, but did not cause inhibition. ► Manually separated softwood bedding contained substantial methane potential.